Mourners carry a child body during a funeral after an Israeli strike on a school housing displaced Palestinians in Gaza City on Saturday. AFP

The dead included "13 children and six women", one of whom was pregnant, said agency spokesman Mahmud Bassal. There were "around 30 injured, including nine children (needing) limb amputations, as a result of an Israeli bombing on Al Zaytoun School C" in Gaza City, he said.

Thousands of displaced people had sought shelter at the school, Bassal said. Israel's military said in a statement the air force had "conducted a precise strike on terrorists who were operating inside a Hamas command and control centre in Gaza City."

It said the target was "embedded inside" the Al Falah School, which is adjacent to the Al Zaytoun School buildings.

An AFP reporter at the scene confirmed that Al-Zaytoun School C had been hit. Witnesses said that before the strike, orphans had gathered there because they were due to receive sponsorship from a local NGO for humanitarian assistance.

Mourners react during a farewell for Mustafa Zakarneh, that was killed during an Israeli raid, in Qabatiya. Reuters

Israel's military did not provide a death toll but said "numerous steps were taken to mitigate the risk of harming civilians, including the use of precise munitions, aerial surveillance and additional intelligence."

It was the latest in a series of Israeli strikes on school buildings housing displaced people in Gaza. A strike on the United Nations-run Al Jawni School in central Gaza on September 11 drew international outcry after the UN agency for Palestinian refugees said six of its staffers were among the 18 reported fatalities.

Agence France-Presse